Behaviors Analysis Of Asphalt Concrete Core Wall Dam With Considering Spatial Differences

The asphalt concrete core wall dam is widely applied all over the world due to its good performance.With the booming development of water conservation and hydropower in China,the domestic asphalt concrete core wall dam is developing to the super high dam and the regions with high altitude,extremely cold climate and strong earthquakes.In the previous calculation of dam stress and deformation,material parameters of dam usually choose the design value.However,the effect of actual construction quality make the dam material parameters different in the dam space,which may affect the finite element calculation results of the dam stress and deformation.Therefore,it is necessary to study on the finite element analysis of the asphalt concrete core wall dam considering the spatial differences in the rockfill material and the overburden cover,so as to improve the accuracy of the finite element analysis of the dam,and provide guidance for dam design in future.The major research achievements of this thesis are as follows:(1)Based on the second development platform UMAT of ABAQUS,the call of Duncan-Chang E-B model in ABAQUS is achieved,and then the static finite element analysis of the asphalt concrete core wall dam which built on the overburden cover under design conditions is calculated.Meanwhile,according to the result of finite element calculation,the stress and deformation of dam and the asphalt concrete core wall are analyzed,and the interaction relationship of stress and deformation between the dam and the overburden cover is also discussed.(2)Considering the spatial difference of dam material and overburden cover,stochastic finite element based method for stress and deformation uncertainties of asphalt concrete core wall dam is proposed.It is according to Monte Carlo probabilistic design method,the distribution law of the asphalt concrete core wall dam stress and deformation is obtained.Compared with the designed condition,the impact of spatial difference on the stress and deformation of dam and core wall is analyzed and the excess probability of stress and deformation are determined.Therefore it provides guidance for the design stage of the dam construction,and provides a new approach for the fine finite element calculation of dam.(3)Hydraulic fracturing mechanism of asphalt concrete core wall is investigated.According to the result of stochastic finite element which consider the spatial difference of dam material and overburden cover,the hydraulic fracturing of asphalt concrete core wall is analyzed,and the impact of spatial difference on hydraulic fracturing of asphalt concrete core wall is determined.The possibility of hydraulic fracturing of the asphalt concrete core wall under different criteria is compared.